fix: flush buffer

Author: diegomarquezp

sdk-platform-java/hermetic_build/library_generation/generate_repo.py

@@ -181,7 +181,7 @@ def write(self, data):
 
     def flush(self):
         if self.buffer is not None:
-            return
+            self.buffer.flush()
         self.original_stream.flush()